Non-contraceptive health benefits of oral contraceptives.

The use of combined oral contraceptives (COCs) is associated with a reduced risk of developing endometriosis, myomas, and endometrial and ovarian carcinoma. The mechanisms involved are multiple; next to ovulation suppression, a reduction in inflammation in the genital tract is involved. This is accomplished through inhibition of the endometrial expression of enzymes related to the biosynthesis of prostaglandin and oestrogen, particularly cyclooxygenase type II (Cox-2) and aromatase. The blockade of these enzymatic systems by COCs explains the beneficial effects of these compounds in treating the symptoms, and halting the progression of myomas, endometriosis and adenomyosis, all of which are characterized by increased inflammation. Inhibition of aromatase and Cox-2 expression in the endometrium by COCs may explain their efficacy in controlling the pain and excessive uterine bleeding caused by these pathologies. The reduction of inflammation in the endometrium may also be the mechanism behind the lower incidence of endometrial carcinoma in COC users. The blockade of ovulation and ovarian steroidogenesis, on the other hand, may explain the lesser incidence of ovarian cancer and the improvement of acne in users. In conclusion, inflammation appears to play a pivotal role in the development of various benign and malignant gynecological diseases. COCs reduce inflammation in the female genital tract by blocking enzymes such as Cox-2 and aromatase.